1. Field of the Invention
The present general inventive concept relates to a system to and method of monitoring a condition of a process tool, and more particularly, to a system to and method of monitoring a condition of a process tool capable of detecting a malfunction or faulty operation of the process tool.
2. Description of the Related Art
Generally, a semiconductor is manufactured by a variety of processes, for example, diffusion-processes, photo-processes, etching-processes, etc. Each process fabricates a wafer using a variety of tools.
The wafer is typically manufactured by moving along a production line. Quality and productivity of the semiconductor are largely affected by a condition of a tool currently fabricating the wafer. If consecutive processes are performed even though errors or malfunctions occur with a semiconductor fabrication device, a production yield is deteriorated and production costs are increased. Therefore, there are proposed a variety of methods for quickly detecting malfunctions or faulty operations of the wafer fabrication device.
An APC (Advanced Process Control) system is indicative of a representative system for monitoring conditions of the wafer fabrication device. Particularly, an FDC (Fault Detection and Classification) system among a variety of APC systems has been widely adapted to monitor the conditions of the wafer fabrication device.
The FDC system receives various process data (e.g., temperature, pressure, and power, etc.) from a communication port or an additional data collector to detect a faulty operation or malfunction of the wafer fabrication device. In this case, the process data is indicative of various stimuli applied to equipment capable of performing a variety of processes for manufacturing the wafer. Upon receipt of the process data, the FDC system compares the received process data with a reference model generated by reference data, such that it can determine a current condition of the wafer fabrication device.
If a faulty operation or malfunction of the wafer fabrication device occurs in the aforementioned monitoring process, the FDC system warns of a problem of the wafer fabrication device or stops operating the production line of the wafer. For example, if the FDC system continuously receiving process data associated with a flow rate of argon (Ar) gas determines that a difference between the flow rate of Ar gas and a reference flow rate is larger than a predetermined error range, it determines that an unexpected error or faulty operation occurs in the process during which the Ar gas is used, such that it generates an alarm signal or sound. Another method for detecting such a faulty operation or malfunction of the semiconductor fabrication device using the APC system has been disclosed in Korean Patent Laid-open Publication No. 2003-0019635.
However, the aforementioned conventional device for monitoring conditions of the semiconductor fabrication device using the APC system does not consider typical faulty data, whereas it samples typical good data and adapts only the sampled good data as reference data, such that it has a disadvantage in that it is unable to correctly estimate current conditions of the semiconductor fabrication device. In more detail, although data may include faulty process data, the aforementioned conventional device wrongly determines that the data is similar to a reference model extracted from good data in such a way that it mistakes the faulty process data for good process data. Furthermore, the aforementioned conventional device mistakes a normal condition of the semiconductor fabrication device for an abnormal condition of the same, such that it stops operating the semiconductor fabrication device, resulting in deterioration of production efficiency.